11β-Hydroxysteroid dehydrogenases in human endometrium

Key reproductive events, such as menstruation and implantation, are considered to be inflammatory processes and glucocorticoids act as anti-inflammatory agents. The balance of expression of types 1 and 2 11β-hydroxysteroid dehydrogenases (11βHSD) controls the availability of cortisol to bind to the glucocorticoid receptor (GR) and mineralocorticoid receptor (MR). Expression profiles of glucocorticoid-metabolising enzymes and their cognate receptors have been characterized in the reproductive tract. We propose that factors that peripherally promote glucocorticoid action are part of an anti-inflammatory response to tissue remodelling in human endometrium. Protein and mRNA expression in endometrium were investigated using immunohistochemistry and quantitative real-time PCR. There was up-regulated expression of 11βHSD-1 at menstruation and in first trimester decidua. 11βHSD-2 and GR were expressed across the cycle. The MR expression pattern across the cycle and in decidua implies progesterone may also play a regulatory role. The precise roles and interactions of these proteins require further investigation.